Question: $\sum\limits_{k=0}^{1 }{{(2-k)}}=$
Explanation: What is the question asking for? $\sum$ tells us to find the sum. The question is asking for the sum of the values of $2-k$ from $k = 0$ to $k = 1$. Evaluating $\begin{aligned} \sum\limits_{k=0}^{1 }{({2-k})}&= (2-0) + (2-1) \\\\ &= 2 + 1 \\\\ &= 3\end{aligned}$ The answer $\sum\limits_{k=0}^{1 }{({2-k})}=3$